13 year old dog who appears to be drinking much more than normal. I haven't actually measured his intake but I am refilling a 2.5 gallon water fountain at least 2-3 times per day now so I'd say at minimum he is drinking 3 gallons of water per day.

His urine is extremely dilute. Specific gravity is very low. The urine is colorless and odorless. It has been this way for a couple years. Senior blood work panels have always been normal. Urinalysis run 2 weeks ago was normal. Tested for Cushings a couple years ago which was negative. Have not repeated the test. He had his teeth cleaned and a tooth extracted about 6 months ago.

Within the last 2 weeks he has been having many more accidents in the house. He appears to know he has to go most of the time because he gets up and moves from where he was laying but he doesn't ask to go out. I find him just standing and peeing. He will stop if I get his attention. He does ask to go out at other times but he is having 2-4 urinary accidents in the house per day. He empties his entire bladder if I don't catch him. He can pee for 3 minutes straight. It's a lot of urine. Today I did find his bed a little wet and then a puddle in the next room so I think he started to go and was able to stop long enough to get up and then move away and finish.

The last trip to the vet revealed he had some back pain. The vet thought maybe this was interfering with his bladder function. We did cold laser therapy and he was on Rimadyl for 2 weeks. Back pain is better but the original issue with peeing is no better and probably worse.

The vet has also brought up the subject of dementia which I suppose is possible but I still think his urine and the amount he is drinking is really abnormal. Any ideas on what is going on? I guess we'll be back at the vet soon.

Usually if the specific gravity is low, the kidneys aren't working properly to concentrate the jrine, that is part of their function. I would think that would show up in the bun and creatinine in the bloodwork though. That is sure a lot of water for him to be drinking, have you tried only putting out a normal amount every day?

I have a large water fountain that he shares with 2 other small dogs and 6 cats. If I stopped refilling the water all the time, the others would never get a drink.

I did measure his water intake once a couple years ago when his urine started to be dilute and it was determined that he was drinking an appropriate amount. I am pretty certain he's drinking more than he was at that time but I think this weekend I will measure his intake as close as possible. I'll see if I can measure his urine output as well. 5 indoor urinations today and I took him outside 8 times on top of that. It's getting out of control. Vet appointment scheduled Monday.

Last specific gravity was 0.010. Admittedly that was at least a year ago at a different vet and if it has been measured since, my new vet hasn't mentioned it. I am very certain it has not improved though and if anything is even lower. This is something we'll check next week for sure though. BUN and Creatinine done in September 2013 prior to a dental cleaning were normal but I don't have values. A previous vet (the one who did the specific gravity) did say he likely had early kidney failure that wasn't showing on the blood work since thyroid was fine and Cushings was negative. This current vet hasn't even mentioned kidney failure and focused on his back pain after ruling out a UTI. I thought she had the records from the previous vet but it is possible she doesn't. I don't know what they sent her.